This invention is a Section 371 national application based on PCT international application PCT/DE2009/001271, filed Sep. 11, 2009, and also claims priority from German application DE 10 2008 049 016.4, filed Sep. 25, 2008, and the contents of both applications are incorporation herein in their entirety
The invention relates to a rotor blade for a wind energy system with at least one flange running in a longitudinal direction from a rotor blade root to a rotor blade tip and to a method for producing the rotor blade. The invention also relates to a laying assistance device for positioning strips of the flange of the rotor blade.
Rotor blades are sufficiently known in the state of the art. The rotor blades of modern wind energy systems have lengths of 60 meters and more. The rotor blades can have diameters of several meters, in particular in the section of the rotor blade root. Rotor blades that are so long and substantially hollow have the problem of achieving sufficient resistance to bulges. In order to increase the buckling resistance of rotor blades, flanges are applied in the longitudinal direction on the inside along the inner wall of the rotor blade of the upper skin and of the lower skin. Furthermore, webs are mounted in the longitudinal direction projecting vertically from the flanges, that are preferably opposite each other in the inner space of the rotor blades. The flanges and webs are themselves endangered by bulges.
The flanges are customarily produced from positioning strips with a constant width in the laminating method. In this method the flanges can be constructed increasingly thinner from the rotor blade root toward the rotor blade tip by gradually ending positioning strips. This results in high flange thicknesses with a high buckling resistance at the rotor blade root and in the direction of the rotor blade tips the thickness of the flanges constantly decreases, as a result of which their buckling resistance also decreases.
In order to achieve a high effectiveness the flanges are constructed to be wide. However, this has the result that the flanges on the one hand cannot be placed into the outermost rotor blade tip and on the other hand much material is needed for the production of the flange strips.